This invention relates to data recorder/reproducer devices of the type employing a limp, flexible disc media.
These data recorder devices typically include a lead screw or worm driven by a stepper motor for translating the recording head relative to the disc. A carriage assembly supporting the head is threadably engaged by the lead screw so that rotation of the lead screw results in translation of the carriage relative thereto. In one such prior recorder, the carriage assembly defines an internally threaded bore nut. The threaded portion of the bore is engaged by the lead screw to translate the carriage. An adjustment member is positioned longitudinally of the threaded bore on the lead screw and a coil spring is positioned between the adjustment member and the bore to preload these members. Pressure is exerted on the lead screw from both sides to compensate for backlash and to prevent decoupling. The adjustment member includes a hex shaped stop which engages the underside or edge of the carriage.
In the assembly of such a lead screw drive and follower carriage assembly, the initial preload of the spring must be adjusted. With the prior device having the hex stop the carraige must be disassembled from the lead screw to rotate the adjustment member. Also, with this prior device it was felt necessary to coat the lead screw with an anti-friction material such as Teflon to improve the start-up frictional characteristics.
It is important that the carriage assembly not become loose on or rock about the lead screw during use or errors in tracking will result. To provide rotational stability, this carriage includes a guide receiving portion defined by upstanding fingers engaging the guide. Due to normal manufacturing tolerances, however, slop or looseness has resulted as well as undesirable frictional characteristics.
A need exists for a relatively simple lead screw follower head carriage for a disc recorder whereby the assembly process is simplified, adjustment is easily made of the initial spring load of the anti-backlash and antidecoupling spring, looseness is essentially eliminated and better frictional characteristics are obtained.